You are right. Excessive consumption can get in the way of creation. However, I think consumption can also inform creation.Excessive consumption can also get in the way of quality consumption.
Analogy: I remember the days when Times Square in New York was a free-for-all of adult themed establishments. Sometimes, this sort of over the top shouting makes you want and appreciate what's being advertised even less.
Analogy with music: I find that many mainstream audiences are immune to many musical subtleties and often have only the crudest understanding of rhythm. Many such people are unable to hold a melody in their heads, much less process complex melodies. Music used to be a special and rare thing to be cherished, sought out, and paid attention to. Now it's a background thing that we largely tune out.
What's really disturbing about reading and writing suffering from this phenomenon is that writing is frozen cognition. If there is so much to be read that we are tuning it out, then what's the point? If we are reading so much that we are reading without deep cognition, then really we are hardly reading at all.